Belzona 5851
HA-Barrier
A heat-activated epoxy coating for in-situ application to hot metal surfaces with minimal preparation to protect against corrosion.
A 100% solids, single-component epoxy coating that cures in contact with hot surfaces and is designed to prevent or protect metal from corrosion under insulation (CUI). Can be easily applied by brush with no weighing or mixing required.
- SeriesBelzona 5000 Series
- Documents3
Overview of Belzona 5851
A 100% solids, single-component epoxy coating that cures in contact with hot surfaces and is designed to prevent or protect metal from corrosion under insulation (CUI). Can be easily applied by brush with no weighing or mixing required.
Key Benefits
Cure activates only when product is heated, providing unlimited working life until applied to hot surfaces
Outstanding performance under elevated temperature conditions including dry heat and steam exposure
No solvents, no shrinkage during cure
Bonds tenaciously even when surface preparation is minimal or substrate is contaminated
Application Areas
What this product handles, grouped by equipment area — each links to the full application.
Tanks & Chemical Containment Areas
3 applications- External pipe & tank corrosion protectionCoating of pipelines prone to corrosion damageLearn more
- Corrosion under insulation (CUI) preventionPrevention of corrosion under insulation (CUI)Learn more
- Hot vessel in-situ external coatingIn-situ external coating of process vessels during service operating at high temperature avoiding production downtimeLearn more
Pipelines
1 applicationTechnical Data
Performance Characteristics
- Heat-activated cure
- Cures only when applied to hot surfaces — unlimited shelf life until applied
- CUI protection on hot metallic surfaces with minimal surface preparation
- Excellent adhesion to manually prepared metals including stainless steel, carbon steel, aluminum, brass, copper
- Good chemical resistance against a wide range of chemicals
- Compatible with Belzona 5841 in overlap areas as a complementary CUI system
- Refer to the attached Product Specification Sheet for full data
Heat-Activated Cure
- Working life
- Unlimited until applied to a hot surface
At 100°C (212°F)
- Touch dry
- 2 - 4 hours
- Full cure
- 24 hours
At 150°C (302°F)
- Touch dry
- 30 - 60 minutes
- Full cure
- 6 hours
Service Temperature Limits
- Application substrate temperature range
- 70°C to 150°C (158°F to 302°F)
- Continuous dry service temperature
- Up to 150°C (302°F)
- For cooler substrates (30°C - 80°C)
- Use Belzona 5841
Mixing & Application
Product PDFs
Gallery
Videos
Frequently Asked Questions
How is Belzona 5851 (HA-Barrier) different from a conventional epoxy?
Belzona 5851 (HA-Barrier) is a single-component, heat-activated coating that cures only when applied to hot surfaces (70-150°C / 158-302°F). It requires no weighing or mixing and has unlimited working life until applied to a hot substrate.
What is the maximum service temperature for Belzona 5851?
Belzona 5851 (HA-Barrier) is thermally stable up to 150°C (302°F) in dry conditions, making it suitable for protecting hot pipework and process equipment from corrosion under insulation (CUI).
Can Belzona 5851 be overcoated with Belzona 5841?
Yes. Belzona 5841 has good adhesion to Belzona 5851 (HA-Barrier) coating in overlap areas, allowing the two products to be used together as a complementary CUI protection system across a range of substrate temperatures.
Related Products
Need Belzona 5851 applied
on your asset?
Our Louisiana team supplies and applies it — with 24-hour support, no shutdown, no hot work.